Element-dependent buckling loads of stiffened panels under cantilevered shear

2026-09-18

AI Summary

研究通过对比不同壳单元在不同条件下的屈曲载荷，解决了加强板在悬臂剪切下屈曲载荷依赖于元素类型的问题。

Abstract

The linearized buckling load of a stiffened panel depends on the stress stiffness its shell element assembles. We read it from exported operators against three truncations of one second variation. The classic pass of ANSYS SHELL181 carries a rotation-rotation block pairing the drilling freedom with the bending rotations and its perturbation pass does not; removing the block recovers the perturbation load factor to 0.02%. SHELL281 carries block and couplings in both passes. Abaqus S4 matches the critical mode of the complete second variation to 1.0000 on the translations and its load factor to 1.7%, against 17% and 34% for the other two forms. On an optimized panel under cantilevered shear a 20-node continuum lies 3% to 6% above that form, S4 and SHELL281, 11% and 23% below both SHELL181 passes and 25% above Abaqus S8R, at the finest meshes. On a conventionally stiffened panel the SHELL181 passes stand 1.0% and 3.5% above the complete form, 9% and 21% at half the rib pitch; under a shear flow, on cylinders, open beams and under axial compression the three forms coincide and no pass parts by more than 0.3%.

Problem

• buckling load
• stiffened panel
• cantilevered shear
• shell element

Innovation

• stress stiffness
• buckling load
• shell element
• cantilevered shear
• Abaqus S4